Field of Invention
The present invention relates generally to the field of current controllers. More specifically, the present invention is related to a novel design for electric motor current controller with negative sequence harmonic suppression.
Discussion of Related Art
The paper to P. C. Kraus titled “Method of Multiple Reference Frames Applied to the Analysis of Symmetrical Induction Machinery” discusses the mathematics and physical implementation of using multiple reference frames for control of motors.
The paper to P. Xiao titled “Multiple Reference Frame-based Control of Three-Phase PWM Boost Rectifiers under Unbalanced and Distorted Input Conditions” discusses implementation of multiple reference frames for control. However, Xiao's implementation is based on straightforward application of the fundamental ideas in the above-referenced paper to Kraus.
The U.S. Patent to Sepe, Jr. (U.S. Pat. No. 7,969,103), also assigned to Electro Standards Laboratories, discloses the use of delay state feedback to enhance performance over a wide speed range for electric motors.
Embodiments of the present invention are an improvement over prior art systems and methods.